递归方法在使用FileWriter时无法正常工作。

huangapple
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英文:

Recursive method doesn't work with FileWriter

问题

  1. 我有一个方法，应该将一个给定目录的结构以树状视图写入文件。但是它不会写入子文件夹及其文件，所以我尝试添加了递归调用，但出于某种原因它不起作用。我该如何修复？
  3. public void readFiles() {
  4.     File baseDirectory = new File(path);
  5.     if (baseDirectory.isDirectory()) {
  6.         try (FileWriter writer = new FileWriter("D:/info.txt")) {
  7.             for (File file : baseDirectory.listFiles()) {
  8.                 if (file.isFile()) {
  9.                     writer.append(" |------ " + file.getName());
  10.                     writer.append("\n");
  11.                 } else if (file.isDirectory()) {
  12.                     writer.append(" |+++++ " + file.getName());
  13.                     writer.append("\n");
  14.                     path = file.getPath().replace("\\", "/");
  15.                     readFiles(); // 递归调用在此处
  16.     
  17.                 }
  18.             }
  19.             writer.flush();
  20.         } catch (IOException ex) {
  21.             ex.printStackTrace();
  22.         }
  23.     }
  24. }
  26. 主类：
  28. public class Runner {
  29.     public static void main(String[] args) {
  30.         TreeViewer treeViewer = new TreeViewer();
  31.         treeViewer.setPath("D:/test");
  32.         treeViewer.readFiles();
  33.     }
  34. }

[输出文件示例: 1]1

英文:

I have a method that should write down in a file a structure of a given directory in a tree view. But it doesn't write down subfolders and their files, so I tried adding a recursive call, but for some reason it doesn't work. How can i fix it?

  1. public void readFiles() {
  2.         File baseDirectory = new File(path);
  3.         if (baseDirectory.isDirectory()) {
  4.             try (FileWriter writer = new FileWriter("D:/info.txt")) {
  5.                 for (File file : baseDirectory.listFiles()) {
  6.                         if (file.isFile()) {
  7.                             writer.append(" |------ " + file.getName());
  8.                             writer.append("\n");
  9.                         } else if (file.isDirectory()) {
  10.                             writer.append(" |+++++ " + file.getName());
  11.                             writer.append("\n");
  12.                             path = file.getPath().replace("\\", "/");
  13.                             readFiles(); // recursive call here
  15.                         }
  16.                 }
  17.                 writer.flush();
  18.             } catch (IOException ex) {
  19.                 ex.printStackTrace();
  20.             }
  21.         }

Main class :

  1. public class Runner {
  2.     public static void main(String[] args) {
  3.         TreeViewer treeViewer = new TreeViewer();
  4.         treeViewer.setPath("D:/test");
  5.         treeViewer.readFiles();
  6.     }
  7. }

[Example of the output file: ][1]

答案1

得分: 0

试试这个。

  1. static void tree(File file, String indent, Writer out) throws IOException {
  2.     out.write(indent + file.getName() + System.lineSeparator());
  3.     if (file.isDirectory())
  4.         for (File child : file.listFiles())
  5.             tree(child, indent + "  ", out);
  6. }
  8. public static void main(String[] args) throws IOException {
  9.     try (Writer out = new FileWriter("D:/info.txt")) {
  10.         tree(new File("D:/test"), "", out);
  11.     }
  12. }
英文:

Try this.

  1. static void tree(File file, String indent, Writer out) throws IOException {
  2.     out.write(indent + file.getName() + System.lineSeparator());
  3.     if (file.isDirectory())
  4.         for (File child : file.listFiles())
  5.             tree(child, indent + "  ", out);
  6. }
  8. public static void main(String[] args) throws IOException {
  9.     try (Writer out = new FileWriter("D:/info.txt")) {
  10.         tree(new File("D:/test"), "", out);
  11.     }
  12. }

huangapple
  • 本文由 发表于 2020年9月10日 05:17:53
  • 转载请务必保留本文链接：https://go.coder-hub.com/63819662.html
  • filewriter
  • io
  • java
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